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研究助交联剂TMPTMA和TAIC用量对高硬度乙丙橡胶(EPDM)混炼胶加工性能和硫化胶力学性能的影响。结果表明,助交联剂TMPTMA不仅有提高硫化速率的作用,也具有一定的软化效果,使混炼胶的流动性提高;随着TMPTMA用量的增加,EPDM硫化胶的硬度、拉伸强度、撕裂强度、100%定伸应力增大,而拉断伸长率和回弹性减小,共混胶的磨耗体积先减小后增大。助交联剂TAIC比TMPTMA的交联反应速度慢,交联密度较高;硬度和定伸应力较高,拉伸强度、撕裂强度、拉断伸长率和耐磨性都有所下降。 相似文献
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研究混炼外场条件对溶聚丁苯橡胶/天然橡胶胶料性能的影响。结果表明:随着转子转速增大,混炼胶的门尼粘度变化不大,FL先增大后减小,F_(max)增大,t_(10)缩短,t_(90)变化不大;硫化胶的邵尔A型硬度、拉伸强度和拉断伸长率增大,撕裂强度减小;胶料的Payne效应先增强后减弱。随着初始混炼温度升高,混炼胶的门尼粘度、FL和F_(max)增大,t_(10)和t_(90)缩短;硫化胶的300%定伸应力、拉伸强度、拉断伸长率和撕裂强度呈减小趋势;胶料的Payne效应明显增强。 相似文献
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采用机械共混法制备丁腈橡胶(NBR)/马来酸酐接枝液体聚丁二烯(MA-LB)并用胶,研究MA-LB对NBR性能的影响。结果表明:随着MA-LB用量增大,胶料的焦烧性能改善,硫化时间延长;低丙烯腈含量NBR胶料硬度和拉断永久变形不变,拉断伸长率逐渐增大,拉伸强度先增大后减小(在MA-LB用量为10份时拉伸强度最大),耐低温性能大幅提高;高丙烯腈含量的NBR胶料硬度变化不大,拉伸强度减小,拉断伸长率和拉断永久变形逐渐增大。MA-LB用量为10份时胶料的高低温压缩回弹性能和耐油性能良好,综合性能较佳。 相似文献
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研究炭黑用量和硫化体系[普通硫化(CV)体系、半有效硫化(SEV)体系、有效硫化(EV)体系和过氧化物(DCP)硫化体系]对顺丁橡胶(BR)硫化胶高温拉伸性能的影响。结果表明:不同炭黑用量的BR硫化胶的50%和100%定伸应力均随着温度的升高而逐渐增大,拉伸强度和拉断伸长率均随着温度的升高而逐渐减小,拉伸强度保持率随着炭黑用量的增大而增大;各种硫化体系的BR硫化胶的50%和100%定伸应力均随着温度的升高而逐渐增大,拉伸强度和拉断伸长率均随着温度的升高而逐渐减小;过氧化物硫化体系的BR硫化胶的拉伸强度较小,但高温下的拉伸强度保持率较大。 相似文献
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乙烯酮(双乙烯酮)是十分重要的化工中间体,其下游产品较多。江苏某化工厂开发生产乙烯酮(双乙烯酮)下游产品三十多个,年生产规模三万多吨,是国内以乙烯酮(双乙烯酮)为中间体生产精细化学品的综合骨干企业。针对乙烯酮(双乙烯酮)下游产品废水特点,该厂结合企业实际,开展了产品优化,结构调整,清洁生产,资源循环利用,节水降耗等工作,从源头削减了污染物的生产。同时投资二千多万元新建预处理装置三套,6000m3/d废水生化处理装置一套,使全厂乙烯酮(双乙烯酮)下游产品的废水得到了有效的治理。 相似文献
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The objective of the study was to explore the effect of the degree of deacetylation (DD) of the chitosan used on the degradation rate and rate constant during ultrasonic degradation. Chitin was extracted from red shrimp process waste. Four different DD chitosans were prepared from chitin by alkali deacetylation. Those chitosans were degraded by ultrasonic radiation to different molecular weights. Changes of the molecular weight were determined by light scattering, and data of molecular weight changes were used to calculate the degradation rate and rate constant. The results were as follows: The molecular weight of chitosans decreased with an increasing ultrasonication time. The curves of the molecular weight versus the ultrasonication time were broken at 1‐h treatment. The degradation rate and rate constant of sonolysis decreased with an increasing ultrasonication time. This may be because the chances of being attacked by the cavitation energy increased with an increasing molecular weight species and may be because smaller molecular weight species have shorter relaxation times and, thus, can alleviate the sonication stress easier. However, the degradation rate and rate constant of sonolysis increased with an increasing DD of the chitosan used. This may be because the flexibilitier molecules of higher DD chitosans are more susceptible to the shear force of elongation flow generated by the cavitation field or due to the bond energy difference of acetamido and β‐1,4‐glucoside linkage or hydrogen bonds. Breakage of the β‐1,4‐glucoside linkage will result in lower molecular weight and an increasing reaction rate and rate constant. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 3526–3531, 2003 相似文献
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我厂3号回转窑(Φ4m×60m)生产线在1996年年底由SP窑(产量912t/d)改为NSP窑(产量1320t/d),预分解系统为四级旋风预热器带离线式分解炉 相似文献
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Conclusions It is significant that the purification on a single passage of viscose through porous ceramic corresponds to the result of a two-stage filtration of it in industrial filter-presses with standard fillings.Kiev Combine. Kiev Technological Institute of Light Industry. Translated from Khimicheskie Volokna, No. 3, pp. 20–22, May–June, 1969. 相似文献
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A refined nonlinear value of the main parameter of a material, i.e., the elongation modulus versus the instant temperature value, was suggested for introduction into the computational algorithm of tempering stresses. 相似文献